A module (10) for validating deposited media items is described. The module comprises: illuminating means (24) for illuminating a deposited media item (20); directing means (34) for directing illuminations from the illuminating means (24) to an examination area (22); optical detecting means (26) for detecting emissions from the deposited media item (20) at the examination area (22), where the emissions are caused by the illuminations; and processing means (32) for processing the detected emissions. The processing means (32) is operable in either a first mode, in which the deposited media type is known, or in a second mode, in which the deposited media type is not known. The illuminating means (24) includes ultra-violet radiation, infra-red radiation, and discrete primary colors.